Hi Bobbie, good to see you posting again , tho' I havent been here much myself.
Just skimmed the comments. Looks like the chorus and bridge have been mostly mentioned , so I'll just look at them.
2nd and 3rd c lines--Seem to kind of contradict. To me , when someone hardens their heart, they get to where they don't let anything bother them anymore, but then in the next line, she falls apart. Possible
'nother line2---
"The others words tore her heart." May not work with your rhythm-pattern-meter tho
I dont see any confusion avout there being two different guys. When you say "the other'
It seems plain.

Bridge--Seems could stand some tweaking in lines 2 and 3 Possibilities

Love was never meant to bring pain
And it isn't love if you feel ashamed
She's holding up and holding on
To things that help to keep her sane

The last 2 lines sound like she's barely holding on, which may be true, Change would seem to make her a little stronger.
Good treatment of a difficult subject. Hope it does well for you